Rail-less cable-driven window glass lifter

ABSTRACT

A simple lift rail-less window lifter ( 1 ) is provided in which a member ( 3 ) linking a window glass ( 2 ) and a cable ( 5 ) is positioned with respect to the window glass in such a way as to avoid jamming of the window glass while it is being raised. A method for assembling a window lifter is also provided.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to automobile cable-driven windowlifters, and in particular to cable-driven window lifters with a linkingmember between the cable and a window glass which is not guided byrails, of the simple lift type.

[0002] In simple lift window lifters, the raising movement of the windowglass is only generated by a cable that is rigidly fixed to the linkingmember.

[0003] Generally, window lifters employing a carrier that is guided in arail are more complicated and more expensive than rail-less windowlifters.

[0004] U.S. Pat. No. 2,987,937 discloses a window lifter that does nothave a guide rail. The window lifter comprises two pulleys, one of whichis driven by a motor. These pulleys are mounted rotatively on a rigidsupport, separated by an axial distance. A cable is slipped into arespective groove of each pulley. The cable carries a linking memberbetween the cable and the window glass. Depending on the direction ofrotation of the motor, the linking member is driven upwardly ordownwardly.

[0005] But that United States Patent does not specify whether the windowlifter is of the simple lift or double lift type.

SUMMARY OF THE INVENTION

[0006] There is consequently a need for a single lift window lifter,with no rail, which allows a linking member to be secured to a windowglass in a way that jamming during lifting can be avoided.

[0007] The invention consequently provides a rail-less window lifter(1), with a single lifting member, comprising:

[0008] a cable; a window glass guide frame; a window glass; a linkingmember rendering the cable and window glass integral, applying a forceto the window glass while it is being raised; in which:

[0009] A is a front lower point of contact of the window glass with theframe;

[0010] B is a rear upper point of contact of the window glass with theframe;

[0011] G is the centre of gravity of the window glass;

[0012] C is the point where said linking member applies force to thewindow glass;

[0013] F is the magnitude of the force applied by the linking member tothe window glass;

[0014] tan φ is the coefficient de friction between the window glass andthe window glass lifter;

[0015] β is the angle of inclination of a window glass guiding part withrespect to the vertical;

[0016] P is a magnitude of weight applied to the window glass;

[0017] {right arrow over (y)} is a unit vector directed in the verticaldirection defined by gravity;

[0018] {right arrow over (x)} is a unit vector directed along thehorizontal direction;

[0019] Rar is the magnitude of the force of the frame on the windowglass at point B, equal to (P−F.(sin β.tan(β+Φ)+cosβ))/(sin(β−Φ)−cos(β−−).tan(β+Φ))

[0020] The position of said point C being defined such that:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \geq {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$

[0021] According to one embodiment, the position of point C is definedsuch that:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} > {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$

[0022] According to a further embodiment, J being an assembly tolerancegreater than 10 mm, the position of point C is defined such that:

|A{right arrow over (G)}·{right arrow over (x)}|−J>|A{right arrow over(C)}·{right arrow over (x)}|

[0023] According to a further embodiment, M being an assembly tolerancegreater than 10 mm, the position of point C is defined such that:${{A{\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq {M + \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}}$

[0024] According to yet a further embodiment, the window lifteradditionally comprises:

[0025] a further linking member rendering the window glass and cableintegral, exercising a lowering force on the window glass; in which:

[0026] D is the point of application of force of the other linkingmember on the window glass:

[0027] the position of point D being defined such that:

|A{right arrow over (D)}·{right arrow over (x)}|≧|A{right arrow over(G)}·{right arrow over (x)}|

[0028] The invention also provides a method for assembling a rail-lesswindow lifter of the simple lift type, comprising: providing a cable, aguide frame for the window glass, a window glass, a linking member forexercising a lifting force on the window glass; rendering said linkingmember integral with the window glass in order to apply force thereto ata point C, the position of said point C being defined by:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \geq {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$

[0029] for a mounted window lifter,

[0030] A being a front lower point of contact of the window glass withthe frame;

[0031] B being a rear upper point of contact of the window glass withthe frame;

[0032] G being the centre of gravity of the window glass;

[0033] C being the point where said linking member applies force to thewindow glass;

[0034] F being the magnitude of the force applied by the linking memberto the window glass;

[0035] tan Φ being the coefficient de friction between the window glassand the window glass lifter;

[0036] β being the angle of inclination of a window glass guiding partwith respect to the vertical;

[0037] P being a magnitude of weight applied to the window glass;

[0038] {right arrow over (y)} being a unit vector directed in thevertical direction defined by gravity;

[0039] {right arrow over (x)} being a unit vector directed along thehorizontal direction;

[0040] securing the cable to the linking member; and inserting thewindow glass into the window glass guiding frame.

[0041] In one embodiment of the method, the position of point C isdefined such that:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} > {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$

[0042] In a further embodiment of the method, J being an assemblytolerance greater than 10 mm, the position of point C is defined suchthat:

|A{right arrow over (G)}˜{right arrow over (x)}|−J>|A{right arrow over(C)}·{right arrow over (x)}|

[0043] In a further embodiment of the method, M being an assemblytolerance greater than 10 mm, the position of point C is defined suchthat:${{A{\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq {M + \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}}$

[0044] According to yet a further embodiment, the method furthercomprises a step of providing an additional linking member exercising alowering force on the window glass; rendering said additional linkingmember integral with the window glass for exercising a lowering force onit at a point D, the position of said point D being defined by:

|A{right arrow over (D)}·{right arrow over (x)}|≧A{right arrow over(G)}·{right arrow over (x)}|

[0045] Further characteristics and advantages of the invention willbecome more clear from the description which follows of some embodimentsof the invention provided by way of example and with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0046]FIG. 1 is a diagrammatic view of one embodiment of the windowlifter according to the invention.

[0047]FIG. 2 shows the forces acting on the window glass of FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0048] There is provided a rail-less window lifter of the simple lifttype, in which a linking member between a window glass and a cable ispositioned with respect to the window glass in such a way as to avoidjamming of the window glass while it is being raised.

[0049]FIG. 1 shows, diagrammatically, the inside of a vehicle dooraccording to the invention. The vehicle door 1 includes the windowlifter. The window lifter comprises a window glass 2 secured to linkingmembers 3 and 4, a cable 5 connecting linking members 3 and 4,direction-changing pulleys 6 and 7 over which the cable passes, and adrum 8 for driving the cable, the drum being coupled to a motor 9. Thewindow lifter further comprises a guide frame 10 for the window glassand a cable tensioner 11.

[0050] The window lifter is of the simple lift type as that part of thecable extending between linking member 3 and pulley 6 is the onlyconnecting element which exercises a lifting force on window glass 2.

[0051] According to the invention, the line of action of linking member3 on window glass 2, which is determined by the direction of the cable,is offset from the centre of gravity G, as shown in FIG. 2. This line ofaction is nevertheless at some distance from the edge of the windowglass to ensure the latter does not get jammed in the frame when thewindow glass is being raised. Relative securing between the linkingmember and a window glass can thus be achieved with relatively lessstrict locational requirements, or with assembly tolerance.

[0052] The window glass frame includes, for example, a guide rail inwhich the window glass slides.

[0053] We shall now define the region where the linking member is placedwith respect to the window glass in order to avoid the window glassjamming in the frame. The various elements of the calculations areidentified on FIG. 2.

[0054] We shall call the lower front corner of the window glass A, therear lower corner of the window glass L, the front upper corner of thewindow glass K and the rear upper corner B. Point G corresponds to thecentre of gravity of the window glass, including the linking member ormembers. First, we shall consider that the contact between the windowglass and window glass frame occurs at A and B. To simplify matters, weshall consider the coefficient of friction at A and at B to be identicalat A and B. The person skilled in the art will obviously be able toadapt the calculations to the case where the frictional coefficients aredifferent. Axis X corresponds to the longitudinal axis of the vehiclewith the door closed. The Y axis corresponds to the vertical axis of thevehicle or the axis that is colinear with the acting force of gravity.

[0055] We shall now define the following parameters:${L1} = {{\underset{\quad {A\quad G}\quad}{}{\cdot \underset{\quad x\quad}{}}}}$${L2} = {{\underset{\quad {A\quad C}\quad}{}{\cdot \underset{\quad x\quad}{}}}}$${L3} = {{\underset{\quad {A\quad B}\quad}{}{\cdot \underset{y\quad}{}}}}$${L4} = {{\underset{\quad {A\quad B}\quad}{}{\cdot \underset{\quad x\quad}{}}}}$

[0056] β is the mean angle of inclination of the window glass guidingpart.

[0057] The forces applied to the window glass in the (x, y) plane are asfollows: $\underset{\quad {Rav}\quad}{}$

[0058] is the force applied at point A on the window glass by the windowframe. $\underset{\quad {Rar}\quad}{}$

[0059] is the force applied at point B on the window glass by the windowframe. $\underset{\quad P\quad}{}$

[0060] represents the weight applied to the complete window glass.$\underset{\quad F\quad}{}$

[0061] represents the drive force applied at points C on the windowglass.

[0062] In the (x, y) reference frame, these forces have the followingcomponents: $ \begin{matrix}\quad \\\underset{\quad {Rav}\quad}{} \\\quad\end{matrix} \middle| \begin{matrix}{{Rav}.{\cos ( {\beta + \phi} )}} \\{- {{Rav}.{\sin ( {\beta + \phi} )}}} \\0\end{matrix} $

[0063] The coefficient of friction f is equal to tan (p. We can alsodefine the frictional cones at A and at B. Forces at A and B should bekept outside of these cones, to ensure the window glass slides withoutjamming.

[0064] We shall now established the equilibrium conditions for which thewindow glass gets blocked by jamming:

[0065] Σ (external forces)=zero

[0066] Σ (Moments with respect to point A)=zero

[0067] We thus obtain the following equations:

Rav*Cos(β+Φ)+F*sin β−Rar*cos(β−Φ)=0  (a)

−Rav*sin(β+Φ)+F*cos β+Rar+sin(β−Φ)=0  (b)

L2*sin β−L1*P+L4*Rar*cos(β−Φ)+L3*Rar*cos(β−Φ)=0  (c)

[0068] For raising the window glass, with L2<L1, we shall deduce fromthese equations a condition on L2 making it possible to obtain slidingof the window glass:

L2>(L1*P−L4*Rar*sin(β−Φ)−L3*Rar*cos(β−Φ))/(F.cos β)

[0069] By calculation, we obtain:

Rar=(P−F.(sin β.tan(β+Φ)+cos β))/(sin(β−Φ)-cos(β−Φ).tan(β+Φ))

[0070] Generally speaking, for raising the window glass, we avoid thecase where L2>L1 as the window glass then will get jammed at the cornersK and L.

[0071] For a window glass lowering force F, with L2>L1, movement isguaranteed until L2=L1.

[0072] For a window glass lowering force F, with L2<L1, jamming of thewindow glass occurs at the corners K and L.

[0073] We consequently preferably situate the linking member that isexercising a lifting force so that the following relation holds:L2>(L1*P−L4*Rar*sin(β−Φ)−L3*Rar*cos(β−Φ))/(F.cos).

[0074] If we wish to guarantee with a greater margin of security,lifting of the window glass without jamming, we can provide thefollowing strict inequality:

L2>(L1*P−L4*Rar*sin(β−Φ)−L3*Rar*cos(β−Φ))/(F.cos β)

[0075] The tolerance regarding positioning of the linking member withrespect to the window glass while assembling the lifting mechanism canconsequently be less strict.

[0076] We can also provide an assembly tolerance J, with respect to theline of action of the weight passing through G, greater than 10 mm. Wecan then additionally employ the following inequality, as a function ofthe tolerance J chosen, for positioning the linking member:

[0077] L1−J>L2.

[0078] We can further provide an assembly tolerance M with respect tothe limit point for jamming, which is greater than 10 mm. We can thenemploy, further, the following inequality as a function of the toleranceM selected, for positioning the linking member:

L2>M+(L1*P−L4*Rar*sin(β−Φ)−L3*Rar*cos(β−Φ))/(F.cos β)

[0079] If a linking member that exercises a lowering force on the windowglass is employed, we can locate this linking member so that therelation L2>L1 holds.

[0080] Where inclination β varies, in particular when the lifting pathof travel is curved with respect to the (x, y) plane, we employ, in ourcalculations for positioning of the linking member, the value of β whichis the most unfavourable for jamming. This consequently ensures that thewindow glass can be raised without jamming.

[0081] It will also be understood that the position of point C is amodelling of the application of forces to the window glass for a linkingmember of a certain width.

[0082] The invention also relates to a method for assembling a windowlifter.

[0083] In this method for assembling a rail-less window lifter of thesimple lift type, the steps are performed of providing a cable, a guideframe for the window glass, a window glass, a linking member forexercising a lifting force on the window glass; rendering said linkingmember integral with the window glass in order to apply force thereto ata point C, the position of said point C being defined by:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \geq {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$

[0084] for a mounted window lifter,

[0085] A being a front lower point of contact of the window glass withthe frame;

[0086] B being a rear upper point of contact of the window glass withthe frame;

[0087] G being the centre of gravity of the window glass;

[0088] C being the point where said linking member applies force to thewindow glass;

[0089] F being the magnitude of the force applied by the linking memberto the window glass;

[0090] tan Φ being the coefficient de friction between the window glassand the window glass lifter;

[0091] β being the angle of inclination of a window glass guiding partwith respect to the vertical;

[0092] P being a magnitude of weight applied to the window glass;

[0093] {right arrow over (y)} being a unit vector directed in thevertical direction defined by gravity;

[0094] {right arrow over (x)} being a unit vector directed along thehorizontal direction;

[0095] securing the cable to the linking member; and inserting thewindow glass into the window glass guiding frame.

[0096] One can obviously employ the other limiting values set out abovefor locating the linking member with respect to the window glass.

[0097] Obviously, the present invention is not limited to the examplesand embodiments described and illustrated, but may be subject tonumerous variations available to those skilled in the art

What is claimed is:
 1. A rail-less window lifter with a single liftingmember, comprising: a cable; a window glass guide frame; a window glass;a linking member rendering the cable and window glass integral, applyinga force to the window glass while it is being raised; in which: A is afront lower point of contact of the window glass with the frame; B is arear upper point of contact of the window glass with the frame; G is thecentre of gravity of the window glass; C is the point where said linkingmember applies force to the window glass; F is the magnitude of theforce applied by the linking member to the window glass; tan Φ is thecoefficient de friction between the window glass and the window glasslifter; β is the angle of inclination of a window glass guiding partwith respect to the vertical; P is a magnitude of weight applied to thewindow glass; {right arrow over (y)} is a unit vector directed in thevertical direction defined by gravity; {right arrow over (x)} is a unitvector directed along the horizontal direction; Rar is the magnitude ofthe force of the frame on the window glass at point B, equal to(P−F.(sin qβ.tan(β+Φ)+cos β))/(sin(β−Φ)−cos(β−Φ).tan(β+Φ)); The positionof said point C being defined such that:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \geq {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$


2. The window lifter of claim 1, wherein: the position of point C isdefined such that:${{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} > {{A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}$


3. The window lifter of claim 2, wherein: J being an assembly tolerancegreater than 10 mm, the position of point C is defined such that:|A{right arrow over (G)}·{right arrow over (x)}|−J>|A{right arrow over(C)}·x|
 4. The window lifter according to claim 2, wherein: M being anassembly tolerance greater than 10 mm, the position of point C isdefined such that:${{A{\overset{arrow}{C} \cdot \overset{arrow}{x}}}} \geq {M + \frac{( {{{{A{\overset{arrow}{G} \cdot \overset{arrow}{x}}}} \cdot P} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{x}}}} \cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} - {{{A{\overset{arrow}{B} \cdot \overset{arrow}{y}}}} \cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}} )}{( {{F \cdot \cos}\quad \phi} )}}$


5. The window lifter according to claim 3, wherein: M being an assemblytolerance greater than 10 mm, the position of point C is defined suchthat:$| {A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}} \middle| {\geq {M + \frac{( | {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {{\cdot P} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{x}}} \middle| {{\cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{y}}} \middle| {\cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}  )}{( {{F \cdot \cos}\quad \phi} )}}} $


6. The window lifter according to one of the preceding claims, furthercomprising: a further linking member rendering the window glass andcable integral, exercising a lowering force on the window glass; inwhich: D is the point of application of force of said other linkingmember (4) on the window glass: the position of point D being definedsuch that: |A{right arrow over (D)}·{right arrow over (x)}|≧|A{rightarrow over (G)}·{right arrow over (x)}|
 7. A method for assembling arail-less window lifter of the simple lift type, comprising: providing acable, a guide frame for the window glass, a window glass, a linkingmember for exercising a lifting force on said window glass; renderingsaid linking member integral with the window glass in order to applyforce thereto at a point C, the position of said point C being definedby:$| {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {\geq | {A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}} \middle| {\geq \frac{( | {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {{\cdot P} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{x}}} \middle| {{\cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{y}}} \middle| {\cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}  )}{( {{F \cdot \cos}\quad \phi} )}} } $

for a mounted window lifter, A being a front lower point of contact ofthe window glass with the frame; B being a rear upper point of contactof the window glass with the frame; G being the centre of gravity of thewindow glass; C being the point where said linking member applies forceto the window glass; F being the magnitude of the force applied by thelinking member to the window glass; tan Φ being the coefficient defriction between the window glass and the window glass lifter; β beingthe angle of inclination of a window glass guiding part with respect tothe vertical; P being a magnitude of weight applied to the window glass;{right arrow over (y)} being a unit vector directed in the verticaldirection defined by gravity; {right arrow over (x)} being a unit vectordirected along the horizontal direction; securing said cable to saidlinking member; inserting the window glass into said window glassguiding frame.
 8. The method according to claim 7, wherein the positionof point C is defined such that:$| {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {> | {A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}} \middle| {\geq \frac{( | {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {{\cdot P} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{x}}} \middle| {{\cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{y}}} \middle| {\cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}  )}{( {{F \cdot \cos}\quad \phi} )}} } $


9. The method according to claim 8, wherein J being an assemblytolerance greater than 10 mm, the position of point C is defined suchthat: |A{right arrow over (G)}·{right arrow over (x)}|−J>|A{right arrowover (C)}·x|
 10. The method according to claim 8, wherein: M being anassembly tolerance greater than 10 mm, the position of point C isdefined such that:$| {A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}} \middle| {\geq {M + \frac{( | {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {{\cdot P} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{x}}} \middle| {{\cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{y}}} \middle| {\cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}  )}{( {{F \cdot \cos}\quad \phi} )}}} $


11. The method according to claim 9, wherein: M being an assemblytolerance greater than 10 mm, the position of point C is defined suchthat:$| {A\quad {\overset{arrow}{C} \cdot \overset{arrow}{x}}} \middle| {\geq {M + \frac{( | {A{\overset{arrow}{G} \cdot \overset{arrow}{x}}} \middle| {{\cdot P} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{x}}} \middle| {{\cdot {Rar} \cdot {\sin ( {\beta - \phi} )}} -} \middle| {A{\overset{arrow}{B} \cdot \overset{arrow}{y}}} \middle| {\cdot {Rar} \cdot {\cos ( {\beta - \phi} )}}  )}{( {{F \cdot \cos}\quad \phi} )}}} $


12. The method according to one of claims 7 to 11, wherein: it furthercomprises a step of providing an additional linking member (4)exercising a lowering force on the window glass; rendering saidadditional member (4) integral with the window glass for exercising alowering force on it at a point D, the position of said point D beingdefined by: |A{right arrow over (D)}·{right arrow over (x)}|≧|A{rightarrow over (G)}·{right arrow over (x)}|